I have a system with 2 sata hard drives, one Linux and one Windows 7. Grub is installed on the linux drive.

I also have two monitors, one HDMI connection and one DVI connection on the same video card. I had the HDMI as the priority screen.

I installed linux Mint 14. As a precaution I always disconnect the windows drive whenever I upgrade Linux.

After installation, if I tried to have both screens connected while booting linux, it would freeze after the grub boot screen.

Also, if I reconnected the windows drive, rebooting would freeze linux after the grub boot loader screen (with only one monitor connected).The answer was to do two things: First, make the DVI screen the primary, and the HDMI the secondary.

Second, install the proprietary tested nvidia driver, and not use the default video driver.

This cured everything, and now my system is good to go, no problems whatsoever.